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        // 翻转数组
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        console.log(reverse([1, 2, 3]));
        console.log(reverse(1, 2, 3));
        //    检测是否为数组
        // (1)instanceof  运算符  它用来是否为数组
        var arr = [];
        var obj = {}
        console.log(arr instanceof Array);
        console.log(obj instanceof Array);
        // (2)Array.isArray(参数);   H5新增的方法  ie9以上版本才支持
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